1. Technical Field
The present invention relates to a joined body, an electronic device, a projector, and a manufacturing method of a joined body.
2. Related Art
For example, in JP-A-2009-206331, a heat transfer member including an exothermic body (a first member), a counter member (a second member), a substrate (a third member), a brazing portion (a first joining layer) which joins the exothermic body and the counter member together, and a metal film (a second joining layer) which joins the counter member and the substrate together is disclosed. Further, a thermal expansion coefficient of the metal film is lower than a thermal expansion coefficient of the substrate and is higher than a thermal expansion coefficient of the counter member, and a groove (a space portion) for allowing thermal deformation is formed in the metal film. According to such a configuration, it is possible to absorb a thermal expansion difference (a difference in an expanded length due to a difference in the thermal expansion coefficient) between the counter member and the substrate, and it is possible to suppress cracks in the metal film.
However, in JP-A-2009-206331, the configuration of the brazing portion is not described in detail, and the thermal expansion difference between the exothermic body and the counter member is not able to be absorbed according to the configuration of the brazing portion, and thus, the brazing portion or the counter member may be damaged. In addition, heat generated from the exothermic body may not be able to be efficiently radiated according to the configuration of the brazing portion.